When playing as Gangplank on solo top you want to gain gold in the best way possible (Use Parley to last hit minions to gain additional gold bonus buy Philosopher's Stone (also gives you mana regeneration bonus for more use of Parley) and Heart of Gold and you can sell this items lately on. Even if you have to keep concentrated on farming just keep an eye on the map and use your ultimate to assist your team and whit a little luck you may also grab a kill. With taking Teleport when you need to shop is good thing so that you don't lose much of exp. and gold.
Later on whit such a gold advantage buy quickly Warmog's Armor and Atma's Impaler, this combination will give you large AD bonus, then The Bloodthirster, Infinity Edge and Phantom Dancer. You can hold in team fight for a long time whit dealing massive amount of damage to your opponents.
Use Teleport too push lanes and assisting your teammates teleporting on ward or minon nearby but do this only if necessary when your team has small chances of winning.

Special thanks to stefanlegend the creator of this build.
Note: Me and stefanlegend have been playing together whit this build and we won a 95% of games played.